Artificial corneas restore sight for the first time
Swedish and Canadian scientists have successfully implanted artificial corneas in patients, with more than half reporting substantially improved vision.
The results were as good as those acheived through normal human donor transplantation.
"This study is important because it is the first to show that an artificially fabricated cornea can integrate with the human eye and stimulate regeneration," said senior author Dr May Griffith of Linköping University.
"With further research, this approach could help restore sight to millions of people who are waiting for a donated human cornea for transplantation."
The biosynthetic corneas have been more than a decade in the making. Finally, over two years ago, Griffith and Professor Per Fagerholm, an eye surgeon at Linköping University, initiated a clinical trial in 10 Swedish patients with advanced keratoconus or central corneal scarring.
Each patient underwent surgery on one eye to remove damaged corneal tissue and replace it with the biosynthetic cornea, made from synthetically cross-linked recombinant human collagen.
Over two years of follow-up, the researchers watched as cells and nerves from the patients’ own corneas actually grew into the implant, resulting in a 'regenerated' cornea that resembled normal, healthy tissue.
Patients didn't experience any rejection reaction or require long-term immune suppression - serious side effects associated with the use of human donor tissue.
The biosynthetic corneas even became sensitive to touch and began producing normal tears to keep the eye oxygenated. Vision improved in six of the ten patients, and after contact lens fitting, vision was comparable to conventional corneal transplantation with human donor tissue.
"We are very encouraged by these results and by the great potential of biosynthetic corneas," said Dr. Fagerholm.
"Further biomaterial enhancements and modifications to the surgical technique are ongoing, and new studies are being planned that will extend the use of the biosynthetic cornea to a wider range of sight-threatening conditions requiring transplantation."